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arXiv 2007.12089hep-phhep-ex
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NLO QCD对在LHC生产的外壳外$\text{t}\bar{\text{t}}\text{W}^+$的纠正

NLO QCD corrections to off-shell $\text{t}\bar{\text{t}}\text{W}^+$ production at the LHC

Ansgar Denner, Giovanni Pelliccioli

摘要:

本文计算了质子-质子碰撞中离壳层$\text{W}^+$玻色子与离壳层顶-反顶对的非线性QCD修正。由于计算是基于过程$\text{p}\text{p}\to {\text{e}}^+ν_{\text{e}}\,μ^-\barν_μ\,τ^+ν_τ\,{\text{b}}\,\bar{\text{b}}$的全矩阵元素,因此包括了所有离壳效应、自旋相关效应和干涉效应。对积分截面的NLO QCD修正约为$20\%$。使用动力学标度,大多数分布的修正是在同一水平上,而一些分布显示出更大的$K$ -因子在相空间的抑制区域。我们根据双极点近似进行了第二次计算。虽然相应的结果同意在百分之几的完整计算的综合横截面,差异可以达到$10\%$和更多的相空间区域,不占主导地位的顶部-反顶生产。因此,壳上计算应仅限于此精度水平。

英文摘要:

We present results of a computation of NLO QCD corrections to the production of an off-shell top--antitop pair in association with an off-shell $\text{W}^+$ boson in proton--proton collisions. As the calculation is based on the full matrix elements for the process $\text{p}\text{p}\to {\text{e}}^+ν_{\text{e}}\,μ^-\barν_μ\,τ^+ν_τ\,{\text{b}}\,\bar{\text{b}}$, all off-shell, spin-correlation, and interference effects are included. The NLO QCD corrections are about $20\%$ for the integrated cross-section. Using a dynamical scale, the corrections to most distributions are at the same level, while some distributions show much larger $K$-factors in suppressed regions of phase space. We have performed a second calculation based on a double-pole approximation. While the corresponding results agree with the full calculation within few per cent for integrated cross-sections, the discrepancy can reach $10\%$ and more in regions of phase space that are not dominated by top--antitop production. As a consequence, on-shell calculations should only be trusted to this level of accuracy.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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